They can't be locked in high-range too?
They can if you pop out the blank and plug in a separately purchased CDL switch. This is what most of us have done. However, truthfully, rarely do we need to lock CDL on 4Hi. Remember, this is a full time 4x4. The viscous coupling suppose to lock up the center automatically during slick conditions behind the scenes. It's not a true 50/50 lock but darn good enough for most folks.